aic79xx_osm.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

		dev->openings =  1 - dev->active;
	}
}

int
ahd_platform_abort_scbs(struct ahd_softc *ahd, int target, char channel,
			int lun, u_int tag, role_t role, uint32_t status)
{
	int targ;
	int maxtarg;
	int maxlun;
	int clun;
	int count;

	if (tag != SCB_LIST_NULL)
		return (0);

	targ = 0;
	if (target != CAM_TARGET_WILDCARD) {
		targ = target;
		maxtarg = targ + 1;
	} else {
		maxtarg = (ahd->features & AHD_WIDE) ? 16 : 8;
	}
	clun = 0;
	if (lun != CAM_LUN_WILDCARD) {
		clun = lun;
		maxlun = clun + 1;
	} else {
		maxlun = AHD_NUM_LUNS;
	}

	count = 0;
	for (; targ < maxtarg; targ++) {

		for (; clun < maxlun; clun++) {
			struct ahd_linux_device *dev;
			struct ahd_busyq *busyq;
			struct ahd_cmd *acmd;

			dev = ahd_linux_get_device(ahd, /*chan*/0, targ,
						   clun, /*alloc*/FALSE);
			if (dev == NULL)
				continue;

			busyq = &dev->busyq;
			while ((acmd = TAILQ_FIRST(busyq)) != NULL) {
				Scsi_Cmnd *cmd;

				cmd = &acmd_scsi_cmd(acmd);
				TAILQ_REMOVE(busyq, acmd,
					     acmd_links.tqe);
				count++;
				cmd->result = status << 16;
				ahd_linux_queue_cmd_complete(ahd, cmd);
			}
		}
	}

	return (count);
}

/*
 * Sets the queue depth for each SCSI device hanging
 * off the input host adapter.
 */
static void
ahd_linux_select_queue_depth(struct Scsi_Host * host,
			     Scsi_Device * scsi_devs)
{
	Scsi_Device *device;
	struct	ahd_softc *ahd;
	u_long	flags;
	int	scbnum;

	ahd = *((struct ahd_softc **)host->hostdata);
	ahd_lock(ahd, &flags);
	scbnum = 0;
	for (device = scsi_devs; device != NULL; device = device->next) {
		if (device->host == host) {
			ahd_linux_device_queue_depth(ahd, device);
			scbnum += device->queue_depth;
		}
	}
	ahd_unlock(ahd, &flags);
}

static u_int
ahd_linux_user_tagdepth(struct ahd_softc *ahd, struct ahd_devinfo *devinfo)
{
	static int warned_user;
	u_int tags;

	tags = 0;
	if ((ahd->user_discenable & devinfo->target_mask) != 0) {
		if (warned_user == 0
		 && ahd->unit >= NUM_ELEMENTS(aic79xx_tag_info)) {

			printf("aic79xx: WARNING, insufficient "
			       "tag_info instances for installed "
			       "controllers. Using defaults\n");
			printf("aic79xx: Please update the "
			       "aic79xx_tag_info array in the "
			       "aic79xx.c source file.\n");
			tags = AHD_MAX_QUEUE;
			warned_user++;
		} else {
			adapter_tag_info_t *tag_info;

			tag_info = &aic79xx_tag_info[ahd->unit];
			tags = tag_info->tag_commands[devinfo->target_offset];
			if (tags > AHD_MAX_QUEUE)
				tags = AHD_MAX_QUEUE;
		}
	}
	return (tags);
}

/*
 * Determines the queue depth for a given device.
 */
static void
ahd_linux_device_queue_depth(struct ahd_softc *ahd, Scsi_Device * device)
{
	struct	ahd_devinfo devinfo;
	u_int	tags;

	ahd_compile_devinfo(&devinfo,
			    ahd->our_id,
			    device->id, device->lun,
			    device->channel == 0 ? 'A' : 'B',
			    ROLE_INITIATOR);
	tags = ahd_linux_user_tagdepth(ahd, &devinfo);
	if (tags != 0
	 && device->tagged_supported != 0) {

		device->queue_depth = tags;
		ahd_set_tags(ahd, &devinfo, AHD_QUEUE_TAGGED);
		printf("scsi%d:%c:%d:%d: Tagged Queuing enabled.  Depth %d\n",
	       	       ahd->platform_data->host->host_no, devinfo.channel,
		       devinfo.target, devinfo.lun, tags);
	} else {
		/*
		 * We allow the OS to queue 2 untagged transactions to
		 * us at any time even though we can only execute them
		 * serially on the controller/device.  This should remove
		 * some latency.
		 */
		device->queue_depth = 2;
	}
}

/*
 * Queue an SCB to the controller.
 */
int
ahd_linux_queue(Scsi_Cmnd * cmd, void (*scsi_done) (Scsi_Cmnd *))
{
	struct	 ahd_softc *ahd;
	struct	 ahd_linux_device *dev;
	u_long	 flags;

	ahd = *(struct ahd_softc **)cmd->host->hostdata;

	/*
	 * Save the callback on completion function.
	 */
	cmd->scsi_done = scsi_done;

	ahd_lock(ahd, &flags);
	dev = ahd_linux_get_device(ahd, cmd->channel, cmd->target,
				   cmd->lun, /*alloc*/TRUE);
	if (dev == NULL) {
		ahd_unlock(ahd, &flags);
		printf("aic79xx_linux_queue: Unable to allocate device!\n");
		return (-ENOMEM);
	}
	if (cmd->cmd_len > MAX_CDB_LEN)
		return (-EINVAL);
	cmd->result = CAM_REQ_INPROG << 16;
	TAILQ_INSERT_TAIL(&dev->busyq, (struct ahd_cmd *)cmd, acmd_links.tqe);
	if ((dev->flags & AHD_DEV_ON_RUN_LIST) == 0) {
		TAILQ_INSERT_TAIL(&ahd->platform_data->device_runq, dev, links);
		dev->flags |= AHD_DEV_ON_RUN_LIST;
		ahd_linux_run_device_queues(ahd);
	}
	ahd_unlock(ahd, &flags);
	return (0);
}

static void
ahd_linux_run_device_queue(struct ahd_softc *ahd, struct ahd_linux_device *dev)
{
	struct	 ahd_cmd *acmd;
	struct	 scsi_cmnd *cmd;
	struct	 scb *scb;
	struct	 hardware_scb *hscb;
	struct	 ahd_initiator_tinfo *tinfo;
	struct	 ahd_tmode_tstate *tstate;
	uint16_t mask;

	if ((dev->flags & AHD_DEV_ON_RUN_LIST) != 0)
		panic("running device on run list");

	while ((acmd = TAILQ_FIRST(&dev->busyq)) != NULL
	    && dev->openings > 0 && dev->qfrozen == 0) {

		/*
		 * Schedule us to run later.  The only reason we are not
		 * running is because the whole controller Q is frozen.
		 */
		if (ahd->platform_data->qfrozen != 0) {

			TAILQ_INSERT_TAIL(&ahd->platform_data->device_runq,
					  dev, links);
			dev->flags |= AHD_DEV_ON_RUN_LIST;
			return;
		}
		/*
		 * Get an scb to use.
		 */
		if ((scb = ahd_get_scb(ahd)) == NULL) {
			TAILQ_INSERT_TAIL(&ahd->platform_data->device_runq,
					 dev, links);
			dev->flags |= AHD_DEV_ON_RUN_LIST;
			ahd->flags |= AHD_RESOURCE_SHORTAGE;
			return;
		}
		TAILQ_REMOVE(&dev->busyq, acmd, acmd_links.tqe);
		cmd = &acmd_scsi_cmd(acmd);
		scb->io_ctx = cmd;
		scb->platform_data->dev = dev;
		hscb = scb->hscb;
		cmd->host_scribble = (char *)scb;

		/*
		 * Fill out basics of the HSCB.
		 */
		hscb->control = 0;
		hscb->scsiid = BUILD_SCSIID(ahd, cmd);
		hscb->lun = cmd->lun;
		mask = SCB_GET_TARGET_MASK(ahd, scb);
		tinfo = ahd_fetch_transinfo(ahd, SCB_GET_CHANNEL(ahd, scb),
					    SCB_GET_OUR_ID(scb),
					    SCB_GET_TARGET(ahd, scb), &tstate);

		if ((ahd->user_discenable & mask) != 0)
			hscb->control |= DISCENB;

		if ((tinfo->curr.ppr_options & MSG_EXT_PPR_IU_REQ) != 0)
			scb->flags |= SCB_PACKETIZED;

		if ((tstate->auto_negotiate & mask) != 0) {
			scb->flags |= SCB_AUTO_NEGOTIATE;
			scb->hscb->control |= MK_MESSAGE;
		}

		if ((dev->flags & (AHD_DEV_Q_TAGGED|AHD_DEV_Q_BASIC)) != 0) {
			if (dev->commands_since_idle_or_otag == AHD_OTAG_THRESH
			 && (dev->flags & AHD_DEV_Q_TAGGED) != 0) {
				hscb->control |= MSG_ORDERED_TASK;
				dev->commands_since_idle_or_otag = 0;
			} else {
				hscb->control |= MSG_SIMPLE_TASK;
			}
		}

		hscb->cdb_len = cmd->cmd_len;
		memcpy(hscb->shared_data.idata.cdb, cmd->cmnd, hscb->cdb_len);

		scb->sg_count = 0;
		ahd_set_residual(scb, 0);
		ahd_set_sense_residual(scb, 0);
		if (cmd->use_sg != 0) {
			void	*sg;
			struct	 scatterlist *cur_seg;
			u_int	 nseg;
			int	 dir;

			cur_seg = (struct scatterlist *)cmd->request_buffer;
			dir = scsi_to_pci_dma_dir(cmd->sc_data_direction);
			nseg = pci_map_sg(ahd->dev_softc, cur_seg,
					  cmd->use_sg, dir);
			scb->platform_data->xfer_len = 0;
			for (sg = scb->sg_list; nseg > 0; nseg--, cur_seg++) {
				bus_addr_t addr;
				bus_size_t len;

				addr = sg_dma_address(cur_seg);
				len = sg_dma_len(cur_seg);
				scb->platform_data->xfer_len += len;
				sg = ahd_sg_setup(ahd, scb, sg, addr, len,
						  /*last*/nseg == 1);
			}
		} else if (cmd->request_bufflen != 0) {
			void *sg;
			bus_addr_t addr;
			int dir;

			sg = scb->sg_list;
			dir = scsi_to_pci_dma_dir(cmd->sc_data_direction);
			addr = pci_map_single(ahd->dev_softc,
					      cmd->request_buffer,
					      cmd->request_bufflen, dir);
			scb->platform_data->xfer_len = cmd->request_bufflen;
			scb->platform_data->buf_busaddr = addr;
			sg = ahd_sg_setup(ahd, scb, sg, addr,
					  cmd->request_bufflen, /*last*/TRUE);
		}

		LIST_INSERT_HEAD(&ahd->pending_scbs, scb, pending_links);
		dev->openings--;
		dev->active++;
		dev->commands_issued++;
		if ((dev->flags & AHD_DEV_PERIODIC_OTAG) != 0)
			dev->commands_since_idle_or_otag++;
		scb->flags |= SCB_ACTIVE;
		ahd_queue_scb(ahd, scb);
	}
}

/*
 * SCSI controller interrupt handler.
 */
void
ahd_linux_isr(int irq, void *dev_id, struct pt_regs * regs)
{
	struct	ahd_softc *ahd;
	struct	ahd_cmd *acmd;
	u_long	flags;
	struct	ahd_linux_device *next_dev;

	ahd = (struct ahd_softc *) dev_id;
	ahd_lock(ahd, &flags); 
	ahd_intr(ahd);
	acmd = TAILQ_FIRST(&ahd->platform_data->completeq);
	TAILQ_INIT(&ahd->platform_data->completeq);
	next_dev = ahd_linux_next_device_to_run(ahd);
	ahd_unlock(ahd, &flags);
	if (next_dev) {
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
		tasklet_schedule(&ahd->platform_data->runq_tasklet);
#else
		ahd_runq_tasklet((unsigned long)ahd);
#endif
	}
	if (acmd != NULL)
		ahd_linux_run_complete_queue(ahd, acmd);
}

void
ahd_platform_flushwork(struct ahd_softc *ahd)
{
	struct ahd_cmd *acmd;

	acmd = TAILQ_FIRST(&ahd->platform_data->completeq);
	TAILQ_INIT(&ahd->platform_data->completeq);
	if (acmd != NULL)
		ahd_linux_run_complete_queue(ahd, acmd);
}

static struct ahd_linux_target*
ahd_linux_alloc_target(struct ahd_softc *ahd, u_int channel, u_int target)
{
	struct ahd_linux_target *targ;
	u_int target_offset;

	targ = malloc(sizeof(*targ), M_DEVBUG, M_NOWAIT);
	if (targ == NULL)
		return (NULL);
	memset(targ, 0, sizeof(*targ));
	targ->channel = channel;
	targ->target = target;
	targ->ahd = ahd;
	target_offset = target;
	if (channel != 0)
		target_offset += 8;
	ahd->platform_data->targets[target_offset] = targ;
	return (targ);
}

static void
ahd_linux_free_target(struct ahd_softc *ahd, struct ahd_linux_target *targ)
{
	u_int target_offset;

	target_offset = targ->target;
	if (targ->channel != 0)
		target_offset += 8;
	ahd->platform_data->targets[target_offset] = NULL;
	free(targ, M_DEVBUF);
}

static struct ahd_linux_device*
ahd_linux_alloc_device(struct ahd_softc *ahd,
		 struct ahd_linux_target *targ, u_int lun)
{
	struct ahd_linux_device *dev;

	dev = malloc(sizeof(*dev), M_DEVBUG, M_NOWAIT);
	if (dev == NULL)
		return (NULL);
	memset(dev, 0, sizeof(*dev));
	init_timer(&dev->timer);
	TAILQ_INIT(&dev->busyq);
	dev->flags = AHD_DEV_UNCONFIGURED;
	dev->lun = lun;
	dev->target = targ;

	/*
	 * We start out life using untagged
	 * transactions of which we allow one.
	 */
	dev->openings = 1;

	/*
	 * Set maxtags to 0.  This will be changed if we
	 * later determine that we are dealing with
	 * a tagged queuing capable device.
	 */
	dev->maxtags = 0;
	
	targ->refcount++;
	targ->devices[lun] = dev;
	return (dev);
}

static void
ahd_linux_free_device(struct ahd_softc *ahd, struct ahd_linux_device *dev)
{
	struct ahd_linux_target *targ;

	del_timer(&dev->timer);
	targ = dev->target;
	targ->devices[dev->lun] = NULL;
	free(dev, M_DEVBUF);
	targ->refcount--;
	if (targ->refcount == 0)
		ahd_linux_free_target(ahd, targ);
}

/*
 * Return a string describing the driver.
 */
const char *
ahd_linux_info(struct Scsi_Host *host)
{
	static char buffer[512];
	char	ahd_info[256];
	char   *bp;
	struct ahd_softc *ahd;

	bp = &buffer[0];
	ahd = *(struct ahd_softc **)host->hostdata;
	memset(bp, 0, sizeof(buffer));
	strcpy(bp, "Adaptec AIC79XX PCI-X SCSI HBA DRIVER, Rev ");
	strcat(bp, AIC79XX_DRIVER_VERSION);
	strcat(bp, "\n");
	strcat(bp, "        <");
	strcat(bp, ahd->description);
	strcat(bp, ">\n");
	strcat(bp, "        ");
	ahd_controller_info(ahd, ahd_info);
	strcat(bp, ahd_info);
	strcat(bp, "\n");

	return (bp);
}